1. Field of the Invention
Embodiments of the present invention are directed to positive airway pressure devices and methods, for example continuous positive airway pressure (CPAP) devices. More particularly, embodiments of the invention are directed to positive airway pressure devices and methods where the flow and/or pressure through each nostril or naris and the patient's mouth may be individually controlled.
2. Background of the Invention
Sleep disordered breathing is common throughout the population. Some sleep disorders may be attributable to disorders of the respiratory tract. Sleep apnea may be a disorder where a person temporarily stops breathing during sleep. A hypopnea may be a period of time where a person's breathing becomes abnormally slow or shallow. In some cases, a hypopnea may precede an apnea event.
Although hypopneas and apneas may have multiple causes, one trigger for these type events may be full or partial blockages in the respiratory tract. In particular, in some patients the larynx may collapse due to forces of gravity and/or due to forces associated with lower pressure in the larynx than outside the body. A collapse of the pharynx, larynx, upper airway or other soft tissue in the respiratory tract may thus cause a full or partial blockage, which may lead to a hypopnea or apnea event.
One method to counter collapse of the larynx may be the application of positive airway pressure, possibly by using a CPAP machine. This may be accomplished in the related art by placing a mask over at least the patient's nose, and providing within the mask a pressure communicated to the pharynx, larynx, or upper airway. The pressure within the pharynx, larynx, or upper airway may be greater than the pressure outside the body, thus splinting the airway open.
CPAP machines are concerned only with the pressure of the gas supplied at the nostrils of the patient. However, gases flowing from a region of high pressure to a region of low pressure will take the path of least resistance. Thus, breathable gases provided to a patient in the related art may flow only or predominantly through an open nostril or naris. Forcing or allowing all the gas flow to move through a single naris may cause patient discomfort, both because of the volume of the flow and because of the drying effects experienced by the naris through which the gas moves. The flow problem may be exacerbated by a patient attempting to mouth breath while using a CPAP machine.